Multifunction DAQ

cancel
Showing results for 
Search instead for 
Did you mean: 

PCI-6115 continuous waveform generation from bufer ?

The PCI-6115 has large (up to 32M available for DAC analog out) FIFO memory. Can I load a waveform into that memory and have the board continuously loop and generate that waveform without requiring further transfers from computer memory ?

If so, could I re-load part of that waveform to modify it while that generation was going on, or would the generation have to be first stopped ?

While continuously generating on one channel, could the other channel's static DC output level be changed ?
0 Kudos
Message 1 of 3
(2,379 Views)
Steve;

You can download the waveform to the on board FIFO, as long as the waveform is not to big so it could fit into the memory space, and have the board outputing it continuously in a loop.
You can change that waveform on the fly, but that will make the transfer data rate system dependent.
You can't do static Output on the other channel while channel 0 is generating the waveform.
Hope this helps.
Filipe
0 Kudos
Message 2 of 3
(2,379 Views)
How would the waveform be changed on the fly ? By using double-bufering and using the computer's memory as the memory where the board is getting its data from ? If so, would double-buffering have to be used for every cycle in the loop or could I dynamically switch between FIFO usage and computer memory buffer usage ?

What happens if the system misses a DMA transfer or does not complete the computer's buffer-to-FIFO transfer before it's time to re-start the next cycle of the generation ? Can that error be ignored and have the board just use the waveform that already exists in its FIFO ?

I'll be generating at 1 MHz with a duration of 100 msec (100k points). What is the total time (including setup overhead) to transfer this many points to the board ?
I'm using ComponentWorks with Delphi.

How does the board know whether to use its internal FIFO buffer for waveform generation or to use the computer's buffer memory during continuous generation ? Is there a software call made to specify this ?

Same questions for the 5411 arb waveform generator.

Thanks,

Steve
0 Kudos
Message 3 of 3
(2,379 Views)